Bluetooth Voice Dial Issue
1) Droid/Milestone supports one-touch voice dialing and full Bluetooth voice conversations.
2) It does not support hands-free dialing via Bluetooth, and Motorola is aware that it does not.
3) On Droid, you can answer a call or initiate the 'last dialed call' by pressing and holding
the call button on your headset.
4) You can initiate voice-dial using the Google Search or Voice Dial options from the phone itself.
5) Voice Dialing cannot be initiated from a headset, you must turn it on from the phone.
6) At this time the using Bluetooth for voice dialing only supports dialing last number.

Will there be an update?
Motorola is currently evaluating possible solutions for providing voicedialing over Bluetooth.

When available?
Motorola does not have a timefame defined for this; however the update will be provided through a software update process. A full featured version may be available via the Android Marketplace